dhcpv4: use iovec for DNR

Another simple conversion to use iovec.

Signed-off-by: David Härdeman <[email protected]>
Link: https://github.com/openwrt/odhcpd/pull/278
Signed-off-by: Álvaro Fernández Rojas <[email protected]>

diff --git a/src/dhcpv4.c b/src/dhcpv4.c
index 62f68538bab2bc995ea1d71b22e0525f960eb2d6..7c18bca5be8dedb48054cff04834815efc2c4182 100644 (file)
--- a/src/dhcpv4.c
+++ b/src/dhcpv4.c
@@ -623,6 +623,8 @@ enum {
        IOV_SERVERID,
        IOV_NTP,
        IOV_NTP_ADDR,
+       IOV_DNR,
+       IOV_DNR_BODY,
        IOV_END,
        IOV_TOTAL
 };
@@ -670,6 +672,9 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
                .code = DHCPV4_OPT_NTPSERVER,
                .len = iface->dhcpv4_ntp_cnt * sizeof(*iface->dhcpv4_ntp),
        };
+       struct dhcpv4_option reply_dnr = {
+               .code = DHCPV4_OPT_DNR,
+       };
        uint8_t reply_end = DHCPV4_OPT_END;
 
        struct iovec iov[IOV_TOTAL] = {
@@ -678,6 +683,8 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
                [IOV_SERVERID]  = { &reply_serverid, sizeof(reply_serverid) },
                [IOV_NTP]       = { &reply_ntp, 0 },
                [IOV_NTP_ADDR]  = { iface->dhcpv4_ntp, 0 },
+               [IOV_DNR]       = { &reply_dnr, 0 },
+               [IOV_DNR_BODY]  = { NULL, 0 },
                [IOV_END]       = { &reply_end, sizeof(reply_end) },
        };
 
@@ -910,7 +917,7 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
                dhcpv4_put(&reply, &cursor, DHCPV4_OPT_DNSSERVER,
                                4 * iface->dhcpv4_dns_cnt, iface->dhcpv4_dns);
 
-       for (size_t opt = 0; a && opt < req_opts_len; opt++) {
+       for (size_t opt = 0; opt < req_opts_len; opt++) {
                switch (req_opts[opt]) {
                case DHCPV4_OPT_NTPSERVER:
                        if (!a)
@@ -923,6 +930,9 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
                        struct dhcpv4_dnr *dnrs;
                        size_t dnrs_len = 0;
 
+                       if (!a || reply_dnr.len > 0)
+                               break;
+
                        for (size_t i = 0; i < iface->dnr_cnt; i++) {
                                struct dnr_options *dnr = &iface->dnr[i];
 
@@ -939,6 +949,9 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
                                }
                        }
 
+                       if (dnrs_len > UINT8_MAX)
+                               break;
+
                        dnrs = alloca(dnrs_len);
                        uint8_t *pos = (uint8_t *)dnrs;
 
@@ -976,8 +989,10 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
                                memcpy(&d4dnr->len, &d4dnr_len_be, sizeof(d4dnr_len_be));
                        }
 
-                       dhcpv4_put(&reply, &cursor, DHCPV4_OPT_DNR,
-                                  dnrs_len, dnrs);
+                       reply_dnr.len = dnrs_len;
+                       iov[IOV_DNR].iov_len = sizeof(reply_dnr);
+                       iov[IOV_DNR_BODY].iov_base = dnrs;
+                       iov[IOV_DNR_BODY].iov_len = dnrs_len;
                        break;
                }
        }